i've had a decent CB as Chelsea in 08.
And in the many, many hours and games i played in 07 i had one player who turned out to be one of the best players in the game but out of the hundreds I saw this is a very small amount.
If we look at Liverpool's current first team how many of those regulars come directly from their academy... Stevie G and Carra are the only ones I can think of off the top o my head, i may be wrong, but it won't be more than a few. It's the same across many top teams in Europe. Obviously there are exceptions like ManU in the 90's Giggs, Beckham, Scholes etc but still they bought players in.
You seem to expect to much from your acacdemy, i don't think you can expect them to create a team of
prem players each time you get a batch.
IMO the situation in FM is pretty close to real life cept for Arsenal who seem to have some kinda Superhuman Factory or sumthin.